Analysis of communication characteristics of Airy vortex beams in turbulent plasma sheath

Abstract

In this paper, a transmission model of power-exponential Airy vortex beams in plasma turbulence is established based on the random phase screen theory, and the information transmission characteristics of Airy vortex beams are compared under the OOK, BPSK, and DPSK modulation modes in free-space optical communication systems. Bit error rates (BERs) were calculated for different power indices (n), undulation variances (<Δn2>), transmission distances, and anisotropy parameters. In addition, the orbital angular momentum multiplexing of Airy vortex beams in the Line-of-Sight multiple input multiple output system under a plasma turbulence environment is investigated. The spectral efficiency (SE) is analyzed for different signal-to-noise ratio (SNR) and radii of the emitting surface, and the effects of the variation in the system's numerical aperture and the power exponent on the SE and the effective degrees of freedom in space are analyzed. The results show that the Airy beam has better turbulence resistance than the Laguerre–Gaussian beam. The power-exponential Airy beam has better transmission performance than the conventional Airy beam. By increasing the anisotropy parameter, the BER of the system decreases. When the <Δn2> and the transmission distance increase, the BER increases. Increasing the SNR, the radius of the launching surface and the choice of power-exponential Airy beams can improve the channel capacity. These findings provide a theoretical basis for the problem of optical signal propagation in plasma turbulence.